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Laser-Etching Photos On To Eggs

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CNC machines are every maker’s dream. Capable of churning out accurate parts from CAD designs with a minimum of manual labor, they’re a great tool to have in the workshop. Alternatively, you can use them for more entertaining pursuits. [Leo]’s project is one of the latter – etching greyscale photos on to eggs. The first thing you’ll need is an egg-compatible CNC machine. The Eggbot is a popular option , else a fourth-axis on an existing machine can also do the job as in [Leo]’s case. Coupling the egg is a delicate task, for which some rubber paper rollers are salvaged from an old printer and put to work. Then, a laser needs to be fitted to the CNC head, and the egg depth mapped with a probe to ensure the entire etching is in focus. Then it’s simply a matter of loading up an image, and turning the greyscale data into the relevant G-code to burn it onto the egg. Using eggs coated in black ink, the results [Leo] achieves are impressive. The eggs would make an amusing Easter gift, or ser

Building a Heavy Duty Open Source Ventilator

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Since the COVID-19 pandemic started, we’ve seen several attempts to create homebrew ventilators designed to address the shortage of these lifesaving machines. Unfortunately, most hackers aren’t terribly experienced when it comes to designing practical medical equipment. So while many of the designs might have appeared functional on the workbench, there’s little chance they’d get used in any official capacity. The open source DP Ventilator is still clearly the product of a couple plucky hackers, but we think it shows a level of design maturity that’s been missing in many of the earlier attempts. Made primarily with 3D printed components, this mechanical device is designed to operate a hand-held manual resuscitator; essentially standing in for a human operator. This makes the design far less complex than if it had to actually pump air itself, not to mention safer for the patient since the resuscitator (often referred to as an Ambu Bag) installed in it would be a sterile pre-packaged i

A Tale of Tutor Texts

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Have you ever had one of those books that let you choose your own adventure? You know, the book will say “The bully tells you to hand over the secret message. If you want to run away, turn to page 48. If you want to fight him, turn to page 70.” While this is normally a staple of children’s literature, there were a series of training books known as Tutor Texts that used the format to teach technical topics. In fact, one of these books was my first introduction to computer programming more years ago than I care to admit. But it wasn’t just computer programming. There were titles from the same publisher about trigonometry, slide rules, and even how to play bridge. I own four of these old books and it got me to thinking about how we deliver information on the web. Maybe these books were ahead of their time. The Advantage Assuming a book like this is well constructed, this is a pretty good idea. A regular book just tells you something and then — maybe — asks you a question or two to see

Hackaday Podcast 082: DJ CNC, NFC Black Box, Sound of Keys, and Payin’ for 3D Prints

Hackaday editors Elliot Williams and Mike Szczys check in on the best hacks from the past week. All the buzz is the algorithm that can reverse engineer your house keys from the way they sound going into the lock. Cardboard construction goes extreme with an RC car build that’s beyond wizard-level. Speaking of junk builds, there’s a CNC mill tipped on its side grinding out results worlds better than you expect from something made with salvaged CD-ROM drives. And a starburst character display is a clever combination of laser cutting and alternative using UV-cured resin as a diffuser. Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments! Direct download (~65 MB) Places to follow Hackaday podcasts: Google Play iTunes Soundcloud Spotify Stitcher RSS Episode 082 Show Notes: New This Week: Running A Successful Hacker Camp In A Pandemic: BornHack 2020 2020 Hackaday Prize Interesting Hacks of the

Creating Kelvin Test Leads for Four-Wire Measurments

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[VoltLog] has a cheap Hantek LCR meter, but it only has two probes. The best resistance and impedance measurements, though, use four wires to improve accuracy. The first order of business was a custom PCB to fit into the connector of the meter, along with a 3D-printed case. Using a four-wire scheme requires unusual alligator clips that don’t electrical short the jaws together. The clips were hard to solder and even harder to strain relief. but [VoltLog] seemed to handle it with little problem. There are some ready-made solutions for this, of course, but the good ones aren’t cheap. Besides, this way, the lead length is exactly what you want and you can control the entire construction, including sheilding and strain releif. If you haven’t run into four-wire sensing before, it is a simple idea. In a normal two-wire measurement, you send a voltage through the device under test and measure the current through the wires. But since you’re using the same pair of wires to deliver the curre

Open Hardware Laptop Built on Power PC ISA

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Since Apple switched to Intel chips in the mid-00s, the PowerPC chips from Motorola and the PowerPC Instruction Set Architecture (ISA) that they had been using largely fell by the wayside. While true that niche applications like supercomputing still use the Power ISA on other non-Apple hardware, the days of personal computing with PowerPC are largely gone unless you’re still desperately trying to keep your Power Mac G5 out of the landfill or replaying Twilight Princess. Luckily for enthusiasts, though, the Power ISA is now open source and this group has been working on an open-source laptop based on this architecture . While development is ongoing and there are no end-user products available yet, the progress that this group has made shows promise. They have completed their PCB designs and schematics and have a working bill of materials, including a chassis from Slimbook. There are also prototypes with a T2080RDB development kit and a NXP T2080 processor, although they aren’t running

Over-Engineered Single Button Timer

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Feature creep is typically something to be avoided, since watching a relatively simple project balloon into a rat’s nest of complexity often leads to ineffective, or even abandoned, projects. On the other hand, if you can maintain a tight focus, it’s not always a bad thing. [cbm80Amiga] shows us how to drill down and add specific features in this single-button timer without losing focus on what the original project was all about. The timer is based on an Arduino Pro Mini and an HX1230 LCD with a simple piezo speaker for audible alerts. A single button controls operation of the timer, with short presses incrementing each digit and long presses moving on to the next digit. Controlling button presses this finely is a project in its own, but then [cbm80Amiga] moves on to other features such as backlight control, low power modes which allow it to operate for around two years on a single battery charge, preset times for various kitchen uses, and different appearance settings. Honestly we